Abstract

A modulation bandwidth approaching 5 GHz in a GaAsquantum wellvertical cavity surface emitting laser with a mushroom mesa structure is reported. The modulation speed and the maximum power of 1.5 mW were limited by device heating. The second harmonic distortion as a function of frequency was measured at an injection current twice threshold and an optical modulation index of 10%, and a peak distortion of about −25 dBc was obtained.